Falls are a significant source of early morbidity and mortality in the aging population, yet the neurological, sen- sory, and motor changes that lead to increased fall risk often escape early identification and intervention. Vital signs are commonly used in clinical settings to assess the cardiovascular system (blood pressure, heart rate), immune system (body temperature), and the respiratory system (respiratory rate) to establish baseline values when initiating care, screen for increased risk of co-morbidities or diseases, and allow for identification and com- munication of changes from baseline between health care professionals across time and locations. No similar vital sign exists for assessing the balance system, which draws upon neurological, sensory and motor functions. Therefore, there is an urgent need for a balance vital sign in order to proactively catch declining balance health before an individual falls. Ideally, this test must be inexpensive, consistent, objective, easy to adopt, and proven sensitive and specific with regard to identifying an individual patient?s risk of falling. Given these design consid- erations and a growing evidence base, quantitative postural control measurement (qPCM) stands out as the most viable candidate to serve as a standardized vital sign for balance health. Our long term goal is the imple- mentation of qPCM as a vital sign in primary care and other clinical settings to track balance health among individual patients over time and across clinical locations. Phase I Segment - Aim 1: Design an inexpensive, easy-to-use qPCM tool suitable for use by physicians, advanced practice providers, and medical assistants in busy clinic settings, using theoretical frameworks for usability and implementation science to inform formative evaluation and stakeholder engagement. Milestone: Completed prototype of qPCM device and implementation toolkit that achieves high initial acceptance from end users and is ready to produce for efficacy testing. Phase II Segment - Aim 2: Assess the initial efficacy of qPCM to better identify patients with a significant decline in balance relative to the standard history and physical exam in the clinical setting. Using a randomized controlled design with randomization by clinic to receive the qPCM tool or use standard of care, test the hypotheses that (a) providers will perceive that it influences their clinical decision-making process, and (b) providers are more likely to recommend further evaluation or treatment for a balance deficit or fall risk when using the qPCM system than without it. The contribution of the proposed project is expected to be quantitative postural control assess- ment and an implementation toolkit to align with workflow in the clinical environment. This contribution will be significant because every patient could receive objective, quantitative postural control assessment at every office visit. Our proposed research is innovative because it uses a stakeholder-centered approach to create an evi- dence-based assessment suitable of becoming a ?vital sign? in the clinical setting and the requisite implementa- tion toolkit to facilitate adoption and uptake of the assessment. We also propose innovative methods to determine whether the assessment influences clinical decision making in practice.